Circuit-breaker.



PATENTBD MAY 26, 1908. LH. SMYTHB.

GIRGUIT` BREAKER'. PrLwATIoN FILED AUG. 17. 190s.

Y s smswnmz'r 1.

PATBNTED MAY'ze, 190s.

yf@ f EDWIN SMYTHE, OF CHICAGO, ILLINOIS, ASSIGNOR TO WESTERN OFCHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

CIRCUIT-annalisa.

specification of Letten; Patent.

Patented May 26, 1908.

Application filed August 17, 1905. Serial No. 274,617.

To all whom it may concern:

Be it known that I, EDWIN H. SMYTHE,

citizen of the United States, residing at Ohicago, in thel county ofCook and State of Illinois, have invented a certain new and usefulImprovement -in Circuit-Breakers, of which.

. the following is a full, clear, concise, and exact description.

My invention relates to an electric circuit breaker, and its object isto provide an iinproved and simple switch mechanism which will be strongand effective `in its switching operation, and capable of carrying heavycurrents, while being` easy to operate and causing com aratively slightthrust or strain on the switc board.

I dispense with the laminated bridging member which is commonly used incircuit breakers, and substitute therefor a solid bridging member, ormembers, adapted to close the circuit between laminze constituting theContact terminals of the electric circuit. More especially, my inventioncomprises circuit terminals each of which is preferably composed of apair of laminated contacts, anda bridging member in two parts, linkedtogether by Ia toggle arrangement, so that when they switch is beingclosed the parts of the bridging member are first brought freely betweenthe 'opposing lamina1A and then spread outward with great pressure tomake t eir contacts.

One of the advantages resulting from my invention is that a very closecontact is made between the bridging member 'and the circuit terminals.Furthermore, when the switch is being closed, the usual carbon shuntterminals make good contact with each other before the bridging memberapproaches suf.- ficiently near the circuit terminals to produce an are,and likewise said carbon blocks remain in close contact While thc switchis being opened until after the circuit is broken through the bridgingmember; said carbon blocksl thus effectively takingthearc both whenthe'switch is being opened and closed.

A further advantage arising from my invention is that, owing to thepeculiar construction thereof, there is very little thrust tending to oen the breaker when it is closed,

land hence t e releasing mechanism may be made lighter than that incommon use, and

l can be more delicately adjusted.

`partly in section, and with parts ELECTRIC COMPANY,

I will describe my invention more -parf ticularly by reference to theaccompanying drawings, in which Figures 1 and 2 are side elevationsshowing the switch in its closed and in its o en position, respectively;Fig. 3 is a front e evation, broken away; Fig. 4 is a sectionalelevation on the line 4.-4 of Fig. 3; Fig.l 5 is a sectional plan viewon the line 5 5 of Fig. 1, with parts omitted in order `to more clearlyillustrate certain parts.

The same letters of reference are used to, vdesignate the same partswherever they are shown.

vIn general Athe switch ofthe circuit breaker comprises a pivoted switcharm a carrying a brid ing member composed of a solid blade or b ades Aadapted to engage and electrically unite the main contact'terininalsOC",

formed of laminas mounted upon blocks ofcopper c c which are secured tothe base b.V

The upper end of the switch arm ma also carry a carbon block c2, and acarbon b ook c. 'may be affixed to the block c, the carbon blocks takingthe are when the switch opens, in a manner well understood.

The sprin0r ated by the handle e. The latch i holds the toggle closed,and said latch is adapted tobe released by the armature lc of theelectromagnet 7c. lhe operation of these parts may d tends. to -open theswitch which is readily closed by the tog rle Z, operfV be readilyunderstood from the drawing, and

is moreover fully described in my application" Serial No. 229,476, filedOct. 21,1904, other suitable means foro erating the switc arm may besubstituted t iereforl` Y Y Upon the copper blocks c c', which in the.

devices in common use constitute' the terinnals of the electric circuit,are mounted main'.

contact terminals C C, respectively. Each of terminals CC comprises apair of contacts, composed .of laminas, the 'o posin faces of. each airbein preferably evele outwardly as s iown at Theterminals C C arepreferably bridged by two solid blades A A held in' the desired relationto each other by togglesj' The blades are here shown as having theircorres l)ending'longitudinal edges parallel and the planes of theirfaces inclined toward each other, forming'substantially a Wedge-shaped 2Y r .Y scares ,bridging member. I."l`he toggles ff whenexi tended thrustthe blades A A in close contact with the beveled edges- CZ of theterminals C C. -Said toggles are pivotally mounted upon a'block g,Iwhich is pivotally secured by .l the pin' h to the arm a, and held inproper relation thereto by the spring m, as best shown in Fig. `ll.

The blades A A are so positioned that they readily pass between theopposing pairs of contacts C C when the circuit is being closed.

' The spreading of the blades to contact with the terminals C (1 isautomatically determined by their reaching a limiting stop n at thefinal stage of their forwardl movement,

whereupon any further forward movement of the arm t carrles the togglesf f to spread the blades apart 'and force them into intimate 'is pivotedtothe block g. The s ring p tends to press the arm o lnwardly, and encecauses .'the'carbon shunt terminals C2 C3 to make contact' earlier andbreak contact later than the main switch members, as the switch isrespectivelyclosed or opened. Said bloelrs y c are thus in close contactwith each other before the circuit is closed through the brid ingmembers A A, and remain in contact wit f each other when the arm c ismoved outward untilafter the circuit through said members A A is broken.4 It is apparent therefore that the carbon blocks eflectively take thearc when the switchopens or closes.

To close the circuit by means of the bridgving member the switch arm ais movedforA ward by the manipulation of' the lever` c. The blades A A,together forming a wedgeshaped bridging member, readily enter the spacebetween the opposing beveled' faces ofv t e main contact terminals C C.Prior to the e nals, t e carbon block c engages closely with the carbonblock c. Theforward movement of the blades A A is limited 'b the stopsn,

whereupon any further forwar movement ofthe arm c will'oerate thetoggles j' f and spread apart the lades A A,l forcing them in ,strongcontact with theV beveled faces C2 of the terminals C C. y t

If, while the s 'tch is closed, ya short circuit shouldconie upon thehue', the armature 7c' of the electromagnct lr will be drawn up andwilltrip the tr'igger 7L, thus releasin the mechanism by whic 1 the 'switchis he d in .closedfposition The switch is fthen 'imme- `diately;'openedbywthel springd. When ythe switch is lin its closed positiorlimthleLmembelrs vo'lesfare very near inastraig 'it liiieiga's tdibwn in Fi 5,and lience there is very littlc thrust tenl ing to open the breaker.

lll

agement of the blades with. said termi- 'are beveled outward Owing tothis fact the releasing. mechanism may be made lighterrthan that incommon use, and may be adjustedmore delicately.

What l claim is:

' l. ln a circuit breaker, the combination 7() with circuit terminalseach`of-which has a pair of'contacts, `the opposing faces of 'which arebeveled outwardly, of a wedge-shaped bridging' member composed of twoparts adapted to be brought forward in between 7'5 each pair of rontactsand then laterally in opposite directions to engage the beveled facesthereof, and means for operating the bridging member to open and close`the circuit.

2. In a circuit breaker, the combination with circuit terminals havingfixed contacts. of a bridging member comprising two l ades connectedtogether bv toggles and mounted to move forward freely inbctween saidcon tants, and means for operating the toggles'at g5 the limit of theforward movement of the blades to spread the blades outwardly againstthe contacts to close 'the circuit 3. In a circuit breaker, `thecombination with circuit terminals each of which has a 9o pair oflaminated contacts, of a bridging member comprising two bladesconnectedtogether bytoggles and mounted to move forward. freely in between eachpair of contacts, and means for operating the toggles at the limit ofthe'forward movement of the blades 2A' to spread the blades outwardlyagainst said contacts to close thecircuit. f

4. ln a circuit breaker, the combination with circuit terminals havingfixed contacts, '100 the opposing faces of which are beveled, of awedge-shaped bridging member comprising two blades connected together bytoggles and mounted toniove forward freely inbe,y tween said contacts,and means for operating` the toggles at the limit of the forward moveyment ofthe blades to spread the blades outwardly agail'ist the beveledfaces of said corail-"jV tants. i

5. ln a circuit breaker, the combina-tien iil@ withrircuit terminalseach having;` a pair ,of ,f fixed contacts, the op osing faces of whihare bcvelerhof a wet ge shaped bridglh member comprising two bladesconnectedtoI f gather-by toga-lcs and mounted to movejfolfi Ward freelyin between each pair of contacts, and nrieans for operating the togglesat {tgie limit of the forward movement of the lila; esJ to spread theblades outwardly against the beveled faces o f saidr contacts. i 12D 6.In a circuit breaker, the combination with circuit terminals each havingajpair of fixed contacts, the o posing faces of, wlviich gf, of a wedge`-y`shaped bridging; member comprising` two blades bonnected together bytog-glee and adapted to be freely brought in between said pairs of comi'ta'cts, means for operating the bridging member, and a stop forlimiting the forward movement of the blades, whcrebyany further closingmovement of the bridging mem-v `eled faces of the fixed contacts, asdescribed.

e bevsubstantially bers is in a lateral direction against t 7. In acircuit breaker, the combination with circuit terminals, voi aairoffixed contacts secured to each of sai terminals, the opposing facesofsaid contacts being beveled outwardly, a switch arn and meansfor'operating the same, a block pivoted to said switch arm, a carbonContact pivoted to said block and electricallyn connected to one circuitterminal and adapted to e age a corresponding carbon contact'seeure t othe other clrcuit terminal, a pair of blades carried b :said block inWedge-shaped relation' to eac tially as described.

' In Witness whereof, I-hereunto subscribe my namethis 22nd day of JulyA. D., 1905.A

A EDWIN H. SMYTHE. Witnesses:

DE WITT C. F.Ainxma,V JOHN G. ROBERTS.

